In search of cancer chemotherapeutic agents for metastatic neuroblastoma, we found bromoacetylcholine to be a hopeful one because we found it inhibits neuroblastoma irreversibly at 0.01 mM and induces cytolysis at 0.03 mM or higher. it is therefore proposed to study the following with bromoacetylcholine: 1. Determination of ED50 and ED99 of bromoacetylcholine to inhibit neuroblastoma in vivo and LD1 and LD50 to kill mice. From these information, therapeutic innex and certain safety factor will be calculated. The ID50 of bromoacetyelholine to inhibit neuroblastoma in vitro will also be determined. 2. Investigation of action mechanism of bromoacetylcholine to inhibit neuroblastoma: (a) is the inhibition of neuroblastoma by bromoacetylcholine due to the binding of bromoacetylcholine to the nicotinic receptor? (b) How many binding sites are there in neuroblastoma cells? (c) Is the inhibition caused by the hydrolyzed product of bromoacetylcholine, bromoacetate? 3. Prevention of muscarinic sites by using muscarinic blocking agents along with bromoacetylcholine to reduce side effects. These blocking agents alone will also be tested to see whether the cell growth will be affected by these agents. 4. Determination of best ways by which bromoacetylcholine can be adminitered to the animal, including the timing and routes of administration. BIBLIOGRAPHIC REFERENCES: Rowell, P.P. and Chiou, C.Y. Chemistry and biological activities of N,N-dimethylaminoethyl acrylate, a choline acetyltransferase inhibitor. J. Med. Chem. In press (1976). Rowell, P.P. and Chiou, C.Y. Inhibition of choline acetyltransferase by tertiary alkylamino ethyl esters. Biochem. Pharmacol. In press (1976).